Bekaert (Belgium)

Better understanding of frictional behaviour of powdered soaps used in dry wire drawing can lead to improvements in wire quality and large savings in energy consumption. The latter is particularly significant given the colossal amounts of energy expended in wire drawing processes. However, there is currently a very limited understanding of the subject, including a lack of quantitative data on soap friction. This is at least in part likely to be due to complex tribological behaviour of the powdered soaps, which is very different from that of lubricating oils. This paper studies frictional behaviour of sodium and calcium powdered soaps, using a ball-on-disc tribometer (ETM rig) incorporating a powder ‘scoop’, and under contact conditions pertinent to die-wire contact in wire drawing. Tests employed a WC ball and C15E steel disc to mimic die and wire materials respectively. Results show that under high sliding conditions, friction coefficient with powered soaps is remarkably low, at 0.03 and 0.04 for sodium and calcium soaps respectively. Friction generally decreased with increasing contact pressure and sliding speed. Post-test analysis of ETM specimens showed the presence of thick soap layers on the rubbed surfaces. However, in ETM tests friction was observed to sharply increase leading to the onset of scuffing, soon after the supply of soap to the contact was interrupted, suggesting that any solid deposited layers are easily removed and cannot exclusively explain the low friction. The observed trends suggest that low soap friction may be due to the ability of the soaps to form low shear stress lubricating films at high contact temperatures which are associated with the harsh conditions of high-speed and high-pressure. The results provide new insights into the frictional behaviour of powdered soaps which can be used to optimise the wire drawing processes as well as a direct input to wire deformation models.

The addition of bed joint reinforcement (BJR) to masonry improves the structural behaviour by limiting crack widths and increasing the post-cracking capacity. However, the design of BJR according to Eurocode 6 does not take into account the material properties, and may lead to uneconomical designs. In this paper, the structural behaviour of reinforced masonry with a truss-type and high-strength wire-type BJR is investigated under thermal contraction loading using macromechanical finite element modelling to compare crack widths in order to assess the design approach of Eurocode 6. Varying wall lengths (12 m, 18 m and 24 m), reinforcements (normal and high strength BJR) and boundary conditions (fixed and sliding) are taken into account. The results show that BJR significantly limits the maximum crack widths by increasing the number of cracks. The simulations show that increased spacing between thermal expansion joints can be allowed beyond the current recommendations of Eurocode 6, optimising the design.

Abstract The renewable energy industry through offshore wind has been growing rapidly with increasing project capacities. To accommodate this huge energy transition demand, the projects are moving towards open sea and deeper water. In line with this trend, various design development and innovation on Floating Offshore Wind Turbine (FOWT) technology are progressing to improve the feasibility as well as the economy of the projects. Mooring system is part of major costs components in Floating Offshore Wind (FOW). Reducing mooring loads is desirable to create more room for optimization of the mooring configuration. This could lead to opportunity for saving on the capital costs, more environmentally friendly solutions through reducing the mooring footprint, as well as better mooring integrity. The innovative polymer spring component has been introduced in the mooring industry that enables significant reduction on the mooring loads if it is properly designed. In this paper, the applicability of polymer spring component in FOW applications is further investigated through mooring case studies utilizing comprehensive design analysis. For this purpose, the VolturnUS-S semi-submersible floating platform design is selected. This reference floating offshore wind turbine is developed by the University of Maine – USA to support the International Energy Agency (IEA) 15-MW reference wind turbine. In total, there are eight individual mooring designs analyzed in this study, which are rooted from two very different base mooring systems. The first base mooring system is a ‘conventional’ steel wire with ground chain semi-taut mooring system. While the second one is based on a ‘more novel’ nylon-based taut mooring system with three different declination angles. For each base mooring configuration above, an alternative mooring configuration is proposed by having the polymer spring as part of the mooring component. Dynamic mooring analysis is performed for both the base and the alternative mooring configurations using the same design load cases, and the results are compared. The mooring assessment is performed using fully coupled dynamic time-domain analysis tools Orcaflex with the hydrodynamic database of the platform generated by the Orcawave. All the proposed mooring systems are designed in compliance with the applicable industrial design codes for the Ultimate Limit State (ULS), while meeting the target allowable platform offsets. It should be noted that this paper focuses on optimizing the mooring system for the ULS scenario only. It is acknowledged that Fatigue Limit States (FLS) may be governing in some projects. The expansion of this work to FLS, however, is outside the scope of this paper but will be explored in future papers. Offshore Ulsan, eastern sea of South Korea is selected as the basis for the operational location for all the case studies presented in this paper. Ulsan and its offshore region are being intensively promoted as one of the hubs for the FOW projects. Hence, the results of this mooring study may provide useful input for the developers of these wind farms to further optimize their mooring systems. The benefits of the polymer spring as a mooring component are demonstrated through the case studies. Promising prospects of combining the polymer spring with synthetic nylon rope for FOW mooring system applications are highlighted. At the end of this paper, conclusions and recommendations for future work are drawn.

Sprayed concrete in combination with rock bolts is successfully being used for permanent rock support in tunnels. The main shortcoming is that sprayed concrete alone is unable to function as the permanent waterproofing with strict requirements on a dry interior tunnel surface. Final linings with precast or cast-in-place concrete with sheet membrane waterproofing represent an excessive structural design in hard rock conditions. The SUPERCON research project (Sprayed sUstainable PErmanent Robotized CONcrete) is currently aiming to improve the sprayed concrete technology to enable a permanent waterproof tunnel lining, based entirely on sprayed concrete. Laboratory and full scale spray application testing include innovative mix designs with significantly reduced cement content. The effects of the use of fly ash and limestone powder binder replacement, hydration accelerators and high-performance shrinkage reducing agents as well as adding of polymer modification to the concrete mix and special steel fibres for the distribution of cracks in the hardened concrete were studied. A significant reduction of the autogenous shrinkage potential, and a reduction in the water transport (capillary suction and permeation) through cracks in the concrete using polymeric modification of the concrete was achieved. The use of shrinkage reducing measures in the mix, combined with anti-dryout measures on the sprayed concrete surface significantly reduce cracking risk. The research results so far indicate the feasibility of a waterproof sprayed concrete without a waterproofing membrane.

Abstract The Grand Paris Express is an urban infrastructure project in the Paris agglomeration. The outer districts, which will be enlarged with 70,000 new flats per year, are to be connected to the public transport network of the core city. At the same time, various economic centres are planned around the city, similar to the La Défense banking centre. The metro lines connect the suburban railways, three airports and various TGV stations as a large ring and with direct connections to other transport hubs. The 19.3 km Grand Paris Express Line 16.1 connects the suburbs north and east of Paris in the Seine‐Saint‐Denis department. The cramped construction sites require modern construction processes that are sustainable and can be implemented quickly. For the fully automatic and completely underground line the client, Société du Grand Paris (SGP), is using segmental linings made of steel fibre concrete. The designer Egis, the contractor Eiffage Génie Civil and the segment manufacturer Bonna Sabla optimised the original solution of the 9.5 m ring in terms of productivity and quality in order to complete the construction site within SGP's desired schedule. For the MC2010 performance class, the segments use C50/60 concrete reinforced with 40 kg/m3 of Dramix high performance steel fibres. The 0.75 mm thin fibres, with a tensile strength of more than 1800 N/mm2, form a massive network of 11.6 km fibres/m3 concrete. The entire project also saves over 10,000 t of CO2 due to less steel consumption.

MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> superconducting wires hold the advantage over traditional NbTi wires of higher temperature operation, at lower cost than high temperature superconductors, and allowing the use of existing winding techniques. The adoption of MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> wires into large-scale applications requires a robust production process yielding long length wires with consistent performance. Bekaert and Epoch wires have developed a scalable powder-in-tube technique capable of producing MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> wires in km lengths. Demonstrating practical current density in a solenoid coil is an essential step towards larger demonstration assemblies and coils, in wind-and-react or react-and-wind configurations. Here, we report on the performance of a compact wind-and-react solenoid coil wound from Bekaert/Epoch wires 1+6 MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> cable, made up of unstabilized, monocore 0.4 mm MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> wires. The coil was tested in a He-vapor cooled VTI inside a 10 T Cryofree magnet, between 10 K and 20 K, and at up to 3 T background field. The coil reached 384 A at 15 K in zero external field, generating a self-field of 1.88 T without quench. The coil was quenched multiple times without damage.

Earth and Space Science Open Archive This preprint has been submitted to and is under consideration at Global Biogeochemical Cycles. ESSOAr is a venue for early communication or feedback before peer review. Data may be preliminary.Learn more about preprints preprintOpen AccessYou are viewing the latest version by default [v1]Are terrestrial biosphere models fit for simulating the global land carbon sink?AuthorsChristianSeileriDJoe R.MeltoniDVivekAroraStephenSitchiDPierreFriedlingsteiniDAlmutArnethDaniel SebastianGolliDAtulJainEmilieJoetzjerSebastianLienertiDDanicaLombardozziSebastiaanLuyssaertJulia Esther Marlene SophiaNabeliDHanqinTianiDNicolasVuichardAnthony P.WalkerWenpingYuanSönkeZaehleSee all authors Christian SeileriDCorresponding Author• Submitting AuthorEnvironment and Climate Change CanadaiDhttps://orcid.org/0000-0002-2092-0168view email addressThe email was not providedcopy email addressJoe R. MeltoniDEnvironment and Climate Change Canada, Canadian Centre for Climate Modelling and Analysis (Victoria, BC)iDhttps://orcid.org/0000-0002-9414-064Xview email addressThe email was not providedcopy email addressVivek AroraCanadian Centre for Climate Modelling and Analysisview email addressThe email was not providedcopy email addressStephen SitchiDUniversity of ExeteriDhttps://orcid.org/0000-0003-1821-8561view email addressThe email was not providedcopy email addressPierre FriedlingsteiniDUniversity of Execter (UK)iDhttps://orcid.org/0000-0003-3309-4739view email addressThe email was not providedcopy email addressAlmut ArnethKIT/IMK-IFUview email addressThe email was not providedcopy email addressDaniel Sebastian GolliDLaboratoire des Sciences du Climat et de l'Enivornment, CEA, CNRS, UVSQiDhttps://orcid.org/0000-0001-9246-9671view email addressThe email was not providedcopy email addressAtul JainUniversity of Illinois, Urbana-Champaignview email addressThe email was not providedcopy email addressEmilie JoetzjerUniversité de Toulouseview email addressThe email was not providedcopy email addressSebastian LienertiDUniversity of Bern Physics Institute Climate and Environmental Physics & Oschger Centre for Climate Change ResearchiDhttps://orcid.org/0000-0003-1740-918Xview email addressThe email was not providedcopy email addressDanica LombardozziNational Center for Atmospheric Researchview email addressThe email was not providedcopy email addressSebastiaan Luyssaert[email protected]view email addressThe email was not providedcopy email addressJulia Esther Marlene Sophia NabeliDMax Planck Institute for MeteorologyiDhttps://orcid.org/0000-0002-8122-5206view email addressThe email was not providedcopy email addressHanqin TianiDAuburn UniversityiDhttps://orcid.org/0000-0002-1806-4091view email addressThe email was not providedcopy email addressNicolas VuichardLSCE-IPSLview email addressThe email was not providedcopy email addressAnthony P. WalkerOak Ridge National Laboratory (DOE)view email addressThe email was not providedcopy email addressWenping YuanSun Yat-sen Universityview email addressThe email was not providedcopy email addressSönke ZaehleMax Planck Institute for Biogeochemistryview email addressThe email was not providedcopy email address